The following topics will be studied: TEAR FILM (Surface characteristics; interaction with hydrogels; analysis of surface active components). CORNEAL ULCERATION (inhibition of secreted collagenase in animals and man by 2 minus macroglobulin; inhibition of collagenase production by cyclic AMP (first messenger and second messenger derivatives). HERPES KERATITIS (efficacy and penetration of adenine arabinoside monophosphate). DRUG DELIVERY (continuation of efficacy studies for IDU and corticosteroid ocuserts). CORNEAL WOUND HEALING (chemistry of scar collagen). CORNEAL NUTRITION (studies of glycogen metabolism in normal and diseased conjunctival and corneal epithelium). IMMUNOLOGY (immunopathologic mechanisms of tissue injury in pemphigoid and vernal conjunctivitis). (h) CORNEAL EPITHELIUM (cyclic nucleotide control mechanisms in the control of endogenous growth and proliferation). BIBLIOGRAPHIC REFERENCES: Allansmith, M.R., Lee, J.R., McClellan, B.H., and Dohlman, C.H.: Evaluation of a sustained release hydrocortisone ocular insert in humans. Trans. Amer. Acad. Ophthal. Otol. 79 (1): 128-136, 1975. Berman, M.B., Dohlman, C.H.: Collagenase inhibitors. Presented at XXIIe Congress Int. D'Ophtalmologie. Arch. d'Ophtal. (Paris) 35:95, 1975.